1. Technical Field
The present disclosure relates to photoelectric conversion devices and methods for making the same, and particularly, to a photoelectric conversion device using a conjugated polymer as an electron donor layer and a method for making the same.
2. Description of Related Art
A conjugated polymer is a polymer having a π bond conjugated system. The conjugated polymer may have a good optical property and semi-conductivity because electrons of the π bonds conjugated system are highly delocalized. Thus, the conjugated polymer has interesting and potential application in a plurality of fields. For example, the soluble conjugated polymer can be used as an electron donor layer commonly fabricated by processing the soluble conjugated polymer into a film shape. The soluble conjugated polymer can be alkoxyl substituted poly p-phenylenevinylene derivatives or alkyl group substituted polythiophene derivatives.
Polyacrylonitrile (PAN) is a high polymer composed of saturated carbon skeleton containing cyano groups (C≡N) on alternate carbon atoms. PAN itself is not conductive but can be pyrolyzed by directly heating to form conjugated polymer. The conjugated polymer has a high conductivity, charge storage property, and charge/discharge efficiency. Thus, the conjugated polymer formed by directly heating the PAN can serve as a cathode active material of the lithium-ion battery.
However, the conjugated polymer formed by directly heating the PAN has a black powder shape, and is insoluble in most solvents. Thus, the application of the conjugated polymer is limited because of the insolubility, and the conjugated polymer is difficult to be processed into a film in the photoelectric conversion device.
What is needed, therefore, is to provide a photoelectric conversion device using the conjugated polymer formed by PAN.